Furfural is being used in petroleum industry as a solvent in refining of lubricating oil since 1933. In the refining process, it is used to separate unsaturated cyclic compounds that have a tough solubility in furfural. Removal of these compounds significantly increases the viscosity index of the lubricating oils & renders the oil resistant to oxidation. Furfural is a selective solvent in the lubricating oil purification throughout the world. More than 50% of the world�s lubricating oil is refined by using furfural.

Another important use of furfural is a solvent in the purification of butadiene, a basic ingredient of synthetic rubber. Furfuryl alcohol, a derivative of furfural is used widely in making foundry sand binders.

Furfural is made from pentosans, which are largely available in corn cobs and sugarcane pith.

The digested bagasse after recovering furfural can be used as a fuel in the sugar factory boilers.

Process of making Furfural - Furfural is a aldehyde derivative of pentosans, found along with cellulose in bagasse. Theoretically, 100 parts of pentose yields 64 parts of furfural. Bagasse contains 17.4% furfural.

The process of manufacture of furfural from bagasse is based on the hydrolysis of the pentosan�s content of these residues in the presence of an acidic catalyst such as sulphuric acid.

USES OF FURFURAL DERIVATIVES -Apart from direct use of Furfural, its derivatives are in demand as under -

1. Furfuryl Alcohol -

Furfuryl alcohol is produced by catalytic hydrogenation of furfural.� It
is widely used to make resins, which bond sand into various shapes for making
the mould.� The use of furfuryl alcohol
resins virtually revolutionised the foundry industry, as it is a �no-bake�
resin, enabling them to eliminate expensive ovens.

Other uses of Furfuryl alcohol includes, as an ingredient in wood adhesive, an impregnating solution for wood, stone, bricks, carbon & graphite to make them denser & stronger in mortars & cements used with bricks & tiles for industrial flooring, in consolidation of sand in oil & gas well to prevent sand plugging the well, in paint strippers for removing coating from metal & in the manufacture of grinding wheels.

2. Tetrahydrofurfuryl Alcohol -

Furfuryl alcohol can be converted into Tetrahydrofurfuryl alcohol, which is an intermediate in the production of plasticisers, herbicides & pesticides; a solvent for many synthetic resins; a solvent for dyeing & finishing textiles & leather; a paint and varnish ingredient and as a carrier for agricultural crop sprays.

3. Furfural resins -

A major use of furfuryl achohol is in the production of resins, which are used to fabricate corrosion-resistant and fire-retardant fibre glass reinforced plastic equipment such as storage tanks, reaction vessels, pipes, ducting, stacks and scrubbers. These types of equipments are used by many industries including chemicals, textiles, paper, petroleum and metallurgical to handle corrosive chemicals.

4. Furans -

Another derivative of furfuryl alcohol is furan, which is used as a chemical intermediate for pharmaceuticals, veterinary medicines, insecticides, herbicides and fire chemicals.

5. Tetrahydrofuran -

A major portion of the furan is converted into tetrahydrofuran, which chemical is used as a solvent in the production vinyl top coatings for upholstery, high quality stereo and computer tapes, cellophane wrapping, poly-urethane coatings for suitcases and rainwear, vinyl films for wrapping fresh meat and vegetables & plastic pipes welding cements and other adhesives. It is also used in the pharmaceutical industry for the production of many drugs and steroids.

6. Polyols -

The major use of Tetrahydrofuran is in the production of polyols, mainly used as components in making high performance poly-urethane lastomers. These poly urethanes in turn are used to make items such as rollers, coating for electrical cables, solid industrial wheels, shoe soles, work gloves, spandex fibre, golf balls, car bumpers, life rafts, ski-boats, wet-lock fabrics, wheels for roller skates & skate boards and snowmobile treads. Polyols are also used as modifiers to manufacture thermoplastic polymers.

7. Residues -

The residue obtained during the manufacture of furfural is used as a glue extender in the manufacture of plywood. This residue is also used in the foundries as sand conditioner.

Goodrich offers Furfural technology from China, which is well established and highly cost-effective.

China has more than 200 Furfural producers and most of the units have a capacity of 500 to 3,000 tons per year. The production capacity is restricted by the availability of rawmaterials. Total capacity of Furfural in China is 300,000 � 400,000 tons per annum and the capacity of Furfuryl alcohol is approximately 200,000 tons per annum. China holds the first place in terms of capacity, output and export amount and has become the biggest producer of furfral, furfuryl alcohol and their processed products.

The project cost to build 3,000 tons capacity Furfural plant will be around USD 3 million, with a pay back period of less than 3 years. The international market price of Furfural is USD 750 per ton and the bagasse requirement is 25,000 tons per year to make 3,000 tons of Furfural. Spent bagasse after removing furfural can be used for Co-generation in the Boiler.